The invention relates to a method and a device for operating a changing converter unit of a converter steel plant, wherein the converter which has become useless due to wear of the refectory material is alternatingly removed for repairs from the converter stand and a converter newly equipped with refractory material is placed in the converter stand in an exchange.
Converters for steel production have a refectory lining which is subjected to high wear due to the high temperatures produced during the blowing process and because of the molten steel and slag. Therefore, it is necessary to replace these refractory linings at intervals. For this purpose, the worn converter is removed from the converter stand and is repaired as required in a repair stand. During this time, the steel production is continued with a second converter having a refectory lining without any defects. Different concepts are known for carrying out this exchange of this worn converter for a useful converter in a changing converter unit. For example, in an essay “Einjährige Erfahrung mit Wechselkonvertern bei Mannesmannröhren-Werke AG im Hüttenwerk Huckigen” [Single year experience with changing converters at Mannesmannröhren-Werke AG in the Hüttenwerk Huckigen] Stahl u. Eisen 104 (1984) Nr. 19, pages 969-976 wherein the converter consists of two converter stands with fixedly mounted support rings, three exchangeable converter vessels, a changing carriage, a break-out stand and a repair stand and a holding stand. The sequence of the changing process which becomes necessary at one of the two converter stands when the converter vessel is worn out, is carried out as follows:
The changing carriage travels under the converter stand of the converter to be exchanged. A lifting platform on the changing carriage receives the converter vessel and lowers it after the separation of the clamping elements from the support ring. The changing carriage now moves the converter vessel to the free break-out and repair stand and lowers it at that location with its lifting platform onto cantilever beams. Subsequently, the changing carriage travels to the holding carrier, receives the newly lined converter vessel which is waiting for its use and has been intermediately stored, and transports it to the free converter stand where it is raised with the lifting platform into the support ring. If the changing processes can be carried out quickly, this means that the same capacity is achieved for the melting area as in a conventional steel plant with three converters.
Austrian Patent AT 406 383 B discloses a changing converter unit consisting of a converter stand, at least two receiving stands as well as conveying means for the converter movable between the converter stand and the receiving stands, wherein at least one receiving stand is constructed so as to be movable transversely of the travel direction of the conveying means. The receiving stands are equipped as holding stands and at the same time also as lining stands. In this known changing converter unit, the changing process is carried out as follows:
Initially, the conveying means constructed with a lifting device and a carrying device for the conveying means is moved into the converter stand underneath the worn converter and this worn converter is pressed with the lifting device out of the support ring. Subsequently, the converter is transported to a receiving stand and is placed therefore for repairs. A receiving stand equipped with lined useful converter, which then acts as a receiving stand, is moved at a right angle relative to the travel direction of the conveying means to such an extent that the empty conveying means pick up the repaired converter, convey it to the converter stand and place the converter stand in the support ring.
Moreover, in the brochure H2/305E 1000/06/03 Ky of the company SMS DEMAG AG “Process lines for stainless steel production” changing converter units with AOD converters in novel steel works are described in which, after existing fasting and media supply means have been separated, the converter vessel is exchanged by means of a crane which lifts it out of the closed support ring and lowers it onto a changing carriage. Alternatively, the support ring is U-shaped and the converter vessel is then initially pushed out with a changing carriage having a lifting device.
In the described method differing methods it must be considered a disadvantage that in all methods initially the connection between the converter vessel and the support ring must be separated and then a complicated changing carriage equipped with a lifting device must be used or, in the event of a change from AOD converters in novel steel works, the crane capacity limits or reduces the possibility of carrying out the method.